Does anyone know the cause (and possibly solution) for emails being received with "spam>" coming up in the preview?

I know it's not in the code, and doesn't come through in the actual body, but emails sent through one provider I use come through with that at the beginning.

I was wondering if it was because i'm using a table so the email will render correctly in Outlook, or possibly because the company logo is before text. I don't find this with other providers that have a similar code.

For reference, the emails i'm sending with this issue come from NationBuilder.

*note: I also see this with some auto-replies that i receive from external contacts